Embodiments relate to a method of fabricating a CMOS image sensor and devices thereof. Some embodiments relate to a method of fabricating a CMOS image sensor which may maximize adhesion, for example between an interlayer insulating film and photoresist.
An image sensor may convert an optical image into an electrical signal. An image sensor may be a Charge Coupled Device (CCD) and/or a Complementary Metal Oxide Silicon (CMOS) image sensor. A CCD may have a matrix of photodiodes (PD) which may convert an optical signal into an electrical signal. A CCD may include a plurality of vertical charge coupled devices (VCCD), a horizontal charge coupled device (HCCD) and/or a sense amplifier. A plurality of vertical charge coupled devices (VCCD) arranged between photodiodes in a vertical direction may transmit charges from photodiodes in a vertical direction. A HCCD may transmit charges from a VCCD in a horizontal direction, and/or a sense amplifier may sense charges from a HCCD and/or may forward charges as an electrical signal.
However, a CCD may complicate a fabrication process due to a relatively complicated driving system, a high power consumption and/or multiple photo steps. Moreover, since integration of a control circuit, a signal processing circuit, an analog/digital converter, and the like, on and/or over a charge coupled device chip may be relatively difficult, making a product smaller may be relatively difficult.
Recently, a CMOS image sensor may have been viewed as a next generation image sensor. A CMOS image sensor may be a device which may employ a switching system where MOS transistors may detect outputs from unit pixels in succession, which may be formed on and/or over a semiconductor substrate having substantially the same number as the number of unit pixels. CMOS technology may include a control circuit and/or a signal processing circuit which may be used as peripheral circuits. CMOS image sensor may have a photodiode and/or a MOS transistor within each unit pixel to detect electrical signals from unit pixels in succession, to produce an image. CMOS sensors may have relatively low power consumption owing to CMOS fabricating technology, and/or a relatively simple fabrication process owing to a relatively small number of photo processing steps. Since a control circuit, a signal processing circuit, an analog/digital converting circuit, and the like, may be integrated on and/or over a CMOS image sensor chip, a CMOS image sensor may be relatively smaller. CMOS image sensors may be used in various applications, such as in a digital still camera, digital video camera, and the like.
A CMOS image sensor may be provided with a device isolation film in a semiconductor substrate to define an active region, photodiodes on and/or over a surface of a semiconductor substrate, a plurality of interlayer insulating films and/or metal lines on and/or over an entire surface of a semiconductor substrate, a color filter, and/or microlenses to focus light. Accordingly, there is a need of a CMOS image sensor, and a method of manufacturing an image sensor, which may maximize adhesion, for example between an interlayer insulating film and photoresist.